ESP8266 tutorial 2 - UART Firmware download

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ESP8266 tutorial 1: introduction of esp8266(esp12e) Wifi module for IoT

If you just got the ESP12e board. You don't have any idea what you do to use it.

I think the first step is downloading firmware which you want to use.

Using the ESP8266 firmware download tool, you can easily download the official SDK firmware.

Before downloading firmware you should prepare followings.

1. 3.3V DC power. You can use power supply if you are in the lab. But if you don't have it, you can use 3.3V regulator board (like this board)
2. PC USB to UART converting board is needed. I'm using UM232H-B board (Here's the datasheet of UM232H-B)
3. ESP8266 download tool. You can download it in here.
4. Breadboard and wires to make circuit.

When you are ready to prepare upper four items. Let's start downloading.

Step 1) Make circuit like following picture.

GPIO0, 2, and 15 are used to select boot mode of ESP8266. this setting is for UART download mode.

This table shows three different boot mode of ESP8266.

GPIO15	GPIO0	GPIO2	Mode	Description
L	L	H	UART	Download code from UART
L	H	H	Flash	Boot from SPI flash
H	X	X	SDIO	Boot from SD-card

Step2) Connect UM232H-B board to PC USB port and power on 3.3V DC power supply.

You should check the COM port number through "Device Manager" in Control panel. In my case, COM3 will be used for ESP8266 communication.

Step3) Run ESP flash download tool on the PC

Step 4) Click "Start" button.

You can see the some information through CMD window and DETECTED INFO and MAC Address in the GUI.

If you can't see the DETECTED INFOR and MAC Address in the GUI and see the FAIL message, your circuit has issue or your esp12e board has issue. Please check them again.

Step 5) Download firmware on the web.

You can find SDKs in this web page

I'll download latest NONOS_SDK in this web page

Step 6) Set the address of bin files

you can find the source and bin files in SDK. I'm not build source code now. I'll download bin file to my ESP12e board. Please open "README.md" file in "ESP8266_NONOS_SDK\bin\at"

And then, find NON-BOOT mode section.

ESP12e has 32Mbit Flash. So I'll use 32Mbit case in this document. (I don't know the difference of 32Mbit mode and 32Mbit-C1 mode. I just tried to 32MBit mode)

According to the README.md file, I can set the address of bin file which I should download into my ESP12e board.

Step 7) Download firmware

Please check the following picture and click "start" button" in order to download firmware.

Step 8) Check whether the downloading is done without any issue.

you can see the Finish message in GUI. The download works well.

I'll explain how to test the downloaded firmware in next article.

If you want know more about the ESP8266 SDK. Please refer to this document.